mitchell



@anni obtint'.

ROBERT MITCHELL,

IMPROVEMENT IN vOr CHICAGO, ILLINOIS.

Letterslatent No. 91,254, lated .Tune 15, 1869.

STEAM-GENERATOR The Schedule referred to in these Letters Patent and making part cf the same.

To all 'whom it mail concern Be it known that I, ROBERT B. M'rcnELL, .of Ghicago, in the county of Cook, and State of Illinois, have invented a new and useful improved Slteam-Generator; and I do hereby declare and make known that. the following is a full, clear, and exact description of the same, reference being had to the accompanying drawings, andthe letters andfigures marked thereon, Vwhich form ,part of this speciiication.

My said invention consists in a novel arrangement of a water-reservoir with a steam-generator, Iwhereby the water is supplied to the generator4 automatically,

and, by means of a self-regulating device, is kept at certain required depth in the generator, so that asmall quantity only of water'is admitted, or remains therein, thus enabling the steam top be generatedvery rapidly,

and heated to a very high temperature with Vbntfv'ery little fuel, while, as the water becomes converted into" steam, and passes outt'o' begutilized as desired', {when-2E.' ever it falls below a certain level, the waiter from4 the supply-reservoir immediately passes in and keeps the requisite quantity in the generator at all times, as hereinafter more fully set forth.

To enable thoseskilled in the ait to makeand use my said invention, l will proceed to describethe same with particularity, making reference, in` so doing, to

the aforesaid drawings, in which- Figure l represents aside elevation of myinvention; Figure 2is a rear view of the same;

Figure 3is a vertical entral'section at theline a: in

iig'. 2,; and l Figure 4 is a section, showing the junction of the l air-vent pipe with the supply-pipe.

Similar letters of reference, 4in lthe several figures, represent the same partsof .my'improvement.

A represents a reservoir, which is connected iwith the steam-generator G'by means of a pipe, B, the reservoir being arranged above, -or at a higher eleva-r tion than the generator, so that the water will descend from the reservoir,through the pipe B, into the said generator, by its own weight, as hereinafter described.

The generator is a dat or shallow circular vessel, as shown, but it may be of any other suitable configuration -or proportion';`but as 'only a small quantity of water. is used in it at once, it may be made. shallow, if desired, and oil a suiiicientsnperticial area to answer the purposes for which it is used.

The steam passes out from the generatorfthrough'a pipe, D, and it may be used for cooking or heatingpurposes, or for any of the uses to which steam may be applied where pressure is not required.

When the stop-cock E,in the tube or pipe B, is turned to shut o ff the communication between the reservoir and the generator, and the screwplug a is inserted properly in the top of the reservoir, as shown, it'then becomes air-tight, so that when the stop-cock E is opened, after filling the reservoir, the water would not iiow down vreadily into the generator, except for an air-tube or vent, F, which extends down from the back ofthe reservoir, exterior thereto, as seen in figs. 1 and 2, `and joins with the connecting-pipe B, just at its elbow, opening into the same in such a manner and position, that when the water wholly fills the horizontal part of the pipe B, that is, when the water in the generator is deep enough to cause it to fill the said horizontal pipe, the end of said tube F, at its junction' with the pipe B, is closed, so as to prevent the entrance ofair through the same into the reservoir, as is clearly shown in lig. 4.

At one end of the reservoir is a glass tube or gauge, b, connected withthe reservoir at each end by tubes c o, to admit the water, into the tube, and show when said reservoir requires filling. Having described the construction of my invention, I will proceed to describe the operation.

'.lo lill the reservoir,'the ,stop-cock E is closed, and .the screw-plug a in the-top rem'oved, and the water is 'poured -in through the aperture,` which is then closed air-tight. v 1 N Whenthe apparatus is to be put in use, the stopcck E is opened, andthe water flows down into the reservoir, the vair entering thet'ube F, and passing up into the reservoir, to displace, the water, until the water rises in thefgenerator high enough to .close or fill the horizontal part of the feeding-pipe B, and when this vhappens from the position where the air-tubes join the pipe, the lower-end of said air-tube is closed by the water, so as to prevent any more air from passing through said pipe F, up into the reservoir, thus making an automatic check 'tothe admission ot' water into the generator, as the water will not descend from the reservoir unless air rises or enters the same to displace it. I

.From this arrangement, it results that the water in the generator is always kept at a depth equal to the soon as the water is converted into steam, and falls below the upper side of the horizontal tube B, air enters through F, until the deficiency is supplied.

It may be observed, that when the air-vent or pipe F isemployed toadmit air into the reservoir, so as to canse the water therein to descend into the generator, the pipe B, or rather that part thereof which enters the generator, should be inclined slightly downward, in entering said generator, so that the end ofthe pipe will always be submerged in the water, although the vent-pipe F may be unclosed.

Or the same end would be attained by having said tube horizontal, and having the vent-pipeV open into the pipe B, a slight distance above the top ot' the horizontal part of the pipe B.

operation of my invention,

What I claim, and desire to secure by Letters Patent, is

The steam generator C, air-tight water-reservoir A, connecting-pipe B, and air-vent tube F, when constructed and arranged substantially as specied.

ROBERT B. MITCHELL.

Witnesses:

H. Bruns, W. E. Manus.

diameter of the pipe B, entering the generator, for as.

Having thus fully described the construction and 

